HP 5526A Operating Note And Program Listings page 9

3. Data via 5526 (0) or Keyboard (1)?
Indicate how data is to be sent to calculator. If transfer is over
the interface direct from the Laser Display, answer "0". If data
is hand entered into the calculator keyboard, answer (1). (Default
= 5526).
4. Foot Spacing?
Distance between measurement points if different from the standard
spacing provided by the angular optics bracket (2.0625 inches).
(Default = 2.0625 inches).
NOTE: At this point, we are ready to input the data. Step 5 will
occur before each new inspection line is begun. Step 6 or Step 7
will occur for each point that is input on the current inspection
line. Step 8 will be reached after all lines have been entered.
5. (+/-) line # ? (+: Away) (-: Toward)
As explained in Application Note 156-2, the line # identifies the
inspection line which is to be measured or edited next. The positive
or negative sign indicates the reference direction of the angular
mount with respect to the interferometer. All lines should be
measured with the same reference direction. A line can be
re-measured simply by re-entering its line # when this question is
asked. Press CONTINUE with no line entry when all lines are completed.
This exits this section. (Default = end of data acquisition).
6. Break Beam and Push PRINT to End.
This message is displayed when data entry directly from the Laser
was selected. When a line has been completed, break the alignment
by passing hand through beam (flashing RESET indicator on display)
and press the "PRINT" switch an additional time on the display. This
will return to Step #5 (new line #). If the beam is broken
accidentally during a line, press the "PRINT" switch and re-enter
the same line # in response to Step 5.
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